Planning and Building Permit Costs and Requirements for An Accessory Dwelling in Menlo Park, CA

At New Avenue we have paid over 30 different types of permits to get residential projects approved.  These are “normal” projects too such as additions, remodels, restorations, accessory dwellings accessory structures and custom homes.

One of the architects who is a partner at New Avenue recently completed the design, permitting and construction of an Accessory Dwelling in Menlo Park, CA.

This is a great starting point if you are researching. Most people have never heard of all these fees.We guarantee your project will be different4though!

Here are our findings on the costs of the permits:

Planning/Zoning: $700.00

 Building Permits For 640sf ADU: $6500.00
 School Impact Fee $1,800.00

Here are our findings on the permit requirements:

Q: What is the zoning district?

A: R1S

Q: What is the allowable coverage? How is it measured

A: Floor Area Limit= 2800sf + 25% of (lot size – 7000sf) = 3560sf

Q: Is there a floor-area ratio (FAR) between the Main Home and the Second Unit? What is it?

A: Building Coverage = 35%

Q: What is the maximum allowed size for the Second Unit?

A: 640 SF

Q: Do chimneys, window boxes, and/or bay windows count toward the square footage of the Second Unit?

A: Yes

Q: Do other structures count toward the existing footprint? What are they?

A: Yes, all covered open or closed spaces are included in the FAL. Building coverage is just for enclosed structures.

Q: Does the basement and/or attic count toward the floor area of the Main Home?

A: Basement no, attic space over a 2 story home higher than 5ft does count.

Q: Can the Second Unit have two floors?

A: Yes, but depends on 9ft wall height limit and 17ft overall height limit

Q: Can the Second Unit have a loft, mezzanine, open storage, closed storage, and/or attic?

A: Yes.

Q: Can the loft be habitable space?

A: No

Q: Can the Second Unit have a basement, workspace, or other area? Do they count toward square footage?

A: Yes, and yes they do count towards overall FAL but not building coverage calculations

Q: What landscaping requirements and exceptions are there

A: None for this project.

Q: Is this a liquefaction zone?

A: No

Q: Is this a fire zone?

A: No

Q: Is this a flood zone?

Flood Zone X – least flooding zone in the county.

Q: Is this an environmental zone?

A: No

Setbacks and Dimensions

Q: What is the front setback?

A: 20ft

Q: What are the side setbacks?

A: 5ft with neighbor’s approval letter; in reality it is 10ft because of easement.

Q: What is the rear setback?

A: 5ft with neighbor’s approval letter; in reality it is 10ft because of easement.

Q: What are the required setbacks to the Main Home?

A: N/A – client would like a separate secondary dwelling unit

Q: What are any other required setbacks? Special setbacks may be needed for creeks, power lines, key or corner lots, etc.

A: None

Q: Are there any setback exceptions?

A: See Above

Q: Can the Second Unit be connected to the Main Home? If not, how far apart do they have to be?

A: Yes can be connected. If not, they need to be 10ft apart.

Q: Can we continue a wall of an existing structure within a setback? Is there a maximum length for walls

A: No.

Q: What is the maximum height limit? Is there a max average height limit? Can we match the height of the existing house?

A: 9ft exterior walls, and 17ft max. height


Q: Do we measure from the sidewalk, the property line, or from somewhere else?

A: Front of house, otherwise see below.

Q: How many parking spaces are required for the Main Home? Sizes? Do they need to be covered? What configuration or access must they have?

A: (E) garage is OK for main house. For Secondary unit: 1 (covered or uncovered); tandem ok; permitted within required interior side yard and within the front yard if no more than 500 sf of the front yard is paved for motor vehicles and a minimum side setback of 18 inches is maintained


Q: How many more new spaces are required for the property? Sizes? Do they need to be covered? What configuration or access must they have? Do they require a border around them?

A: None. The new parking spot in the driveway will suffice.

Q: Is there a turning radius or other parking rule to test?

A: None.


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